Foot fins



FOOT FINS Filed Jan. 14, 1958 \K 1: mullum.

\r I 1' ErM-HI-m W. VON BISKUPSKY FIG. I

FIG. 2

Dec. 18, 1962 United States Patent 3,068,499 FOOT FINS Wassily von Biskupsiry, Santa Monica, Calif. (R6. Box 2001, Hollywood 28, Calif.) Filed Jan. 14, 1958, Ser. No. 708,932 3 Claims. (Cl. 9--309) This invention relates to swimming fins and is particularly concerned with a reversible such fin.

The contemporary foot fins are attached before entering the water and are taken off upon leaving the water. Since, in order to be effective, the fin-portion of these articles must have an effective length, as well as width, this portion extends far forwardly from the feet. Walking forwardly is hence sometimes considerably impeded and is always awkward. Upon entering or leaving the water the fins hinder Walking in the marginal water even more than they impede walking on land. For, in addition to the clumsiness of the'protruding fin itself, the walker now has to overcome the waters resistance on the fin every time he lifts a foot. As a consequence, most wearers of swimming fins walk backwards, at least when entering or leaving the water.

In order to resolve these, and other, problems, the present invention resides, among other concepts, in constructing a foot fin in two main portions. In one portion, the foot itself is inserted and firmly seated and gripped. The other portion constitutes the fin or web itself. Preferably this latter portion is defined and outlined by a pair of laterally spaced cantilever beams, or side arms.

Direct connection of the fin to the foot-holding portion is made by means of a centrally located laterally protruding pivot and, by disengageable, or detent-type devices on each side of the article, on the edges of each of the longitudinal sides of the front portion and the back end portion, of the foot-holder, passing thru the foot-holding portion into the fin. Although not strictly necessary and not of the essence of the invention, rugged duty detent means may also be provided at the peak'of the front and rear ends of the shoe portion, but are optional, these detents serving only to prevent undesired upward and downward displacement of the fin from the shoe when locked'to the fin. Thus, the fincan be fixed to the foot-holding portion in either a forwardly or a backwardly pointing attitude, since the detent devices are of a type which are easily manipulatable.

In the forwardly protruding attitude of the fins the device resembles the conventional swimmers fin but is readily transformable into an improved configuration or mode.? To this end, the wearer merely releases the detent devices, lifts his foot, and manually rotates the fin portion downwardly and backwardly thru an arc of substantially 180. In its rotated position, the fin is then fixed to the foot-holder by the rear detents.

Since the fin-portion now is directed rearwardly, the wearer now has no protuberance in front of him and can Walk in a normal, unimpeded manner on land and enter the water. Therein, he reaches down and releases the detent means at the back of the foot-holder, rotates the fin-portion downwardly and forwardly through substantially 180 of arc, and engages the detents in the front region of the footholder. The swim-fin is now again in its forwardly-protruding position, ready for use in swimming.

.-Upon leaving the water, the wearer reverses the last- 3,fifi8,499 Patented Dec. 18, 1962 mentioned procedure so as to position the fins rearwardly on his feet.

, Preferably, the quickly-disconnectible detent means consists of a novel bolt and socket arrangement, although the inventive concepts do not exclude the possibility of employing equivalent means for this purpose.

An exemplificatory embodiment of these, and other, concepts is illustrated in the accompanying drawings and is described hereinafter in conjunction with said drawings, but it is to be understood that the scope of the invention is by no means limited to the specific design disclosed. In fact, and in law, the ambit of the invention is that which is set forth by the sub-joined claims defining the configurational essences of the invention.

In these drawings,

FIG. 1 is a plan view of the improved finned-article;

FIG. 2 is a side view of the novel article, with the finportion in its forwardly-directed attitude, also indicating the path of movement of the fin portion from the one attitude to the other;

FIG. 3 is a side view of the article with the fin directed rearwardly on the foot, that is, in a position reversed from the foregoing;

FIG. 4 is a plan view of the disengageable detent means, and

FIG. 5 is a longitudinal section thru this connection on line 55 of FIG. 4.

Referring now tothe species depicted representationally in the drawings, FIG. .1 shows the foot-holder a into which the foot is inserted, as usual. Through a pivot or hinge means 0, one on each side of a, part a is associated with the cantilever arms, shown, onthe web or fin member b. This figure illustrates the article in the finforward configuration, with portion b protruding ahead of the wearer and therefore a hindrance to easy or proper walking. The detents d are situated on both the front region and on the back region of foot-holder a. I I

FIG. 2 makes it manifest as to how parts d position and hold parts a and b in the forwardly protruding attitude. The dash or broken lines indicate part b in two intermedi ate, transitional positions occupied during the downward rotation of of are, this rotation positioning the fin behind the foot in a rearwardly protruding position,-the latter position being indicated in FIG. 3. Means d are here also employed to rigidly fix or lock the fin b to part a disengageably. v

In FIGS. 4 and 5, the novel nature of the connecting means 0! is detailed. As shown, there is a bolt e which is embedded in part a. The head of the bolt is backed or packed by means which may consist of the same sort of material as that ofpart a. If desired, however, part may consist of a coiled spring, a yieldably resilient elastorner such as sponge rubber, or the like.

A perpendicular actuator or arm g, having a knob h on its upper extremity, is mounted in a bore or slot k shown in part a and reaches or advances and retracts, the threaded end. of the bolt through the agency of a coarse, or low-pitch, thread in the inner end of the aperture in the adjacent wall of the shoe, this threadand other detritus. Barrier or filler m may well consist of sponge rubber.

The correspondingly coarselythreaded opening n in the-part b is adapted to firmly engage the threaded end of the bolt when the latter is advanced thereinto. The resiliently-compressible material then expands and holds the bolt stationary in n without danger of accidental loosening turning thereof and disengagement of the fin from the shoe. In order to enable the bolt to urge out of n any otherwise interfering or blocking material, such as sand, bore or slot n extends fully thru this portion of part b. The co-engagement of the threaded portion of the bolt with the threads in the opening is adequate to substantially prevent the fin from twisting to any detrimental degree in the lateral direction, that is, from torquing under torsional loads. Such co-engagement and arrangement is also adequate to substantially prevent any detrimental absence amount of longitudinal fiexure of the fin, especially if ribs are present or if the edges are vulcanized or otherwise hardened or thickened.

Arm 3 can be rotated A turn or 90, if desired, to obtain deep seating, but it is actually only necessary to rotate it 60 to obtain a'sufficient amount of seating.

Although, for the sake of concreteness, certain specific materials, shapes, relative dimensions and other parameters have been mentioned hereinabove, it is to be understood that such specificities do not constitute the invention or in any wise limit same, except as required by the scope of the annexed claims.

Preferably, the bolt is /2 inch in diameter with a lead of two inches, and a minimum pitch of 4 inch. A rotation of not less than 60, that is, not less than Ms of a revolution, but preferably 90, will advance such a bolt up to /2 inch, which is efiective to bridge the gap between the shoe and the fin, the gap being preferably not over 4 inch. Such rotation will cause the bolt to engage fully A inch into the similarly coarsely-threaded socket in the fin arm.

However, it is also practicable, if desired, to employ a bolt the diameter of which is inch with a lead of 3 inches and a pitch of 4 inch. A rotation of no less than 60 and preferably 90, will advance such bolt up to inch (which is A of said three inches), and such bridges gaps up to inch wide, penetrating inch into the fin. If the lever is to be rotated exactly 60, I prefer to employ a bolt /2 inch in diameter with a three inch lead and Ainch pitch and 4 threads per inch, minimum. The advance of this bolt is also /2 inch with /6 of a revolution, as is well known.

Having thus disclosed my invention and at least one 7 mode of realizing same, what I claim as novel and inventive and hereby secure to myself by US. Letters Patout is:

,l. A 180 reversible swimming fin combination, comprising: a shoe-like portion coextensive with the human foot; a fin having a pair of laterally spaced arms protruding from its inner end-portion and embracing the sides of the shoe-like portion; a pivot pin protruding laterally from the medial portion of each side of the shoe-like portion, each pivot pin pivotally engaging an arm of the fin to the adjacent side of the shoe-like portion, the exterior surface of the pivotal region ahead of, behind, below and abovethe region of pivotal engagement, being free of protrusions and obstructions that would impede the swinging'of the fin about said pivots through a lower arc of 180, so that the fin can be reversed 180? in direction of pointing with respect to the foot; each lateral side of the shoe-like portion bearing protractable and retractable bolt means directed laterally of the shoe-like portion at loci lying on the lower edges of each side of said portion ahead of and behind the pivotal region for anchoring the arms to the shoe-like portion in substantial coplanarity with the foot and preventing both torquing and revolution of the fin when in protracted mode; apertures in the inner face of each arm aligned with the adjacent bolt means so as to receive the protracted bolt; and means carried by each bolt and by the apertures in the sides of the shoe-like portion for advancing each of the bolt means through the supporting side of the shoe-like portion and into the aligned aperture in the arm; the bolt means being retractable into the confines of the shoe-like portion and the sides of the latter being free of protrusions to enable the fin to be unlocked and downwardly swung through 180 of are from a first bolt-locked position occupying a continuation of the plane of the foot, into a second bolt-locked position, 180 from the first position, and also in substantially the plane of the foot.

2. An 180 reversible swimming fin combination, comprising; a shoe-like portion substantially coextensive with the human foot; a fin having a pair of laterally spaced arms protruding longitudinally from the inner end-portion of the fin and embracing the sides of said shoe-like portion; a pivot-pin protruding laterally from the medial portion of each side of the shoe-like portion, each pivot pin pivotally engaging the adjacent arm of the fin to the corresponding side of the shoe-like portion; the exterior surface of the pivotal region on the shoe-like portion, and on the arms, in the region ahead of, behind, below and above the region of pivotal engagement being free of obstructions to the swinging path of the fin throughout an 180 arc of travel of the fin so as to enable reversal of the location of the pivoted fin with respect to the foot thereby to enable the fin to be downwardly swung from a leading, substantially horizontal position to a trailing, substantially horizontal position," both positions being substantially'coplanar with the plane of the foot; retractable and protractable bolt means mounted in the lateral sides of the shoe-like portion and extending substantially horizontally, a first pair of said bolt-means being located on said sides forwardly of the pivot region and a second pair of said bolt-means being located on said sides rearwardly of the pivot region; and an aperture in the inner end of each of said arms adjacent eachof said bolts for receiving and engaging the protracted adjacent bolt, each of said bolts being retractable into the confines of the sides of the shoe-like portion so as to then clear a path for the downward swinging of said fin through 180 from a first horizontal position to a second horizontal position; and means attached to each bolt for rotating same sufiiciently to eifectively protract same into the adjacent aperture and to retract the bolt into the confines of the sides of the shoe-like portion, whereby'said fin can be moved through a downward 180 are from front to rear of the shoe-like portion and in both positions being free of and unsupported by the leg of the wearer and supported against both lateral torsion and longitudinal fiexure only by the engagement of respective ones of said side mounted bolt-means in the respective ones of said apertures.

3. An 180 reversible swimming fin combination, comprising: a shoe-like portion coextensive with the human foot; a fin having a pair of laterally spaced arms protruding longitudinally from its inner end-portion and embracing the sides of said shoe-like portion; a pivot-pin protruding laterally from the medial portion of each side of the shoe-like portion, each pivot pin pivotally engaging the adjacent arm of the fin to the corresponding side of the shoe-like portion; the pivotal region on both the shoelike portion and on the arms in the region ahead of,

behind, below and above the region of pivotal engagement being free of obstructions to the swinging path of the fin throughout an 180 arc of travel of the fin so as to enable reversal of the location of the pivoted fin with respect to the foot thereby to enable the fin to be downwardly swung from a leading substantially horizontal position to a trailing, substantially horizontal position, both positions being substantially coplanar with the plane of the foot; a pair of longitudinally spaced slots in each of the sides of said shoe-like portion on opposite sides of said pivot pin; a laterally extending bore at the bottom of each slot, and opening on the outer face of the shoe-like member and having an inward recess in the shoe-member; a protract able and retractable bolt mounted in each of said bores; an aperture in the inner end of each of said arms adjacent each of said bolts for receiving the protracted adjacent bolt; and resilient-compressible means at the inner end of each of said bores located behind the bolt-head and adapted to be resiliently compressed by the retracted bolt and to expand upon protraction of the bolt and then to hold the bolt stationary in the adjacent aperture and prevent tnrning of the bolt about its axis.

References Cited in the file of this patent UNITED STATES PATENTS Messinger Mar, 7, 1944 De Corlieu Mar. 11, 1952 Schmitz Jan. 10, 1956 FOREIGN PATENTS Italy Sept. 20, 1955 Italy Feb. 20, 1957 

